Advancing type well packer



June 28, 1960 R. H. BLOOD ET AL ADVANCING TYPE WELL PACKER June 2s, 1960 R. H Loon AL 2,942,667

ADVANCING TYPE WELL PACKER 2 Sheets-Sheet. 2

Filed March 7, 1957 Robert H. Blood Inventors Harold C. Bridwell ByUL Attorney United States Patent O 2,942,667 ADVANCING TYPE WELL PACKER Filed Mar. 7, 1957, ser. No. `644,546

s claims. (C1. 16s-rs1) This invention relates to a removable inflatable packer unit used in the drilling and operation of a well. It relates more particularly to an inatable packer that automatically advances downwardly step-wise in a well bore as drilling progresses with no sliding friction between the packer and the wall of the well bore.

ln conventional oil and gas well drilling operations in which a well hole or bore is drilled in the earth in order to locate formations or strata from which oil or gas may be obtained it is quite frequently advantageous and desirable to isolate the area in which `the bit is drilling from the remainder of the annular space between the drill pipe and the walls of the well bore. It is known that by reducing the hydrostatic pressure on the face of the formation being drilled, that drilling efliciencies will be greatly increased, yet it is necessary to maintain relatively high hydrostatic pressures on the formations in the bore hole. One of the methods tried to obtain this result has been the use of a packing element combined with independently acting spring elements with the spring elements forcing the packer out against the walls of the well bore. The lower end of the packing element is sealed and secured to the drill pipe. As the drill pipe advances downwardly in the hole, the packing element likewise Was intended to slide downwardly in contact with the wall of the well bore. This sliding action proves quite detrimental to the packing element and due to the wear and tear of the sliding motion, it is impossible to maintain an adequate seal in the Well bore. Other methods such as the use of inated packers rather than spring loaded packers have been attempted. The inated packer was secured to the drill pipe and as the drilling progressed the inflated packer would slide down the walls of the Well bore. However, in most cases the friction between the inated packer and the wall of the well bore was too great to permit the packer to slide downward. ln those few instances where the packer would slide downward, v

the abrasive action of the packer against the bore wall rendered the packer ineifective as a sealing medium. The combination of the spring loaded packer and the inflation packer have also been tried but the use was not successful due also largely to the friction between the packer andthe wall preventing the sliding; and if thepacker did slide, the`relatively rough surface of the bore Ahole wall soon Wore away the packer to such an extent that a seal could no longer be obtained. Other methods have likewise failed to be completely satisfactory. The present vinvention has eliminated these objections.

In vthe 'present invention an inatable packer assembly is slidably mounted upon and around a drill stem pipe or tubular support which has yan ination means for inflating the packer and in a xed interval above the ination means on the drillpipe, 'a deflating means for deiiating the packer. After the packer has been infiated it remains in a fixed and sealing position while the drill Vstem passes downwardly through thepacker assembly until the deating means is at the same depth as the packer at which time the packer is deflated. The deice ated packer then slides down the drill pipe Where it is stopped at the inflation means which automatically reiniiates the packer. This operation is repeated automatically as the drilling progresses, and the only action required by the operator or driller to insure continuous stepwise advance is to maintain fluid pressure continuously within the drill stem.

In a preferred embodiment an inflatable elastic packer is mounted on a slidable sleeve or packer mandrel which is concentric to and surrounds a tubular support or drill stem. Drilling fluid from the bore of the drill stem passes through an iniiation valve and a conduit in the wall of the drill stem and inates the packer. A hydrostatic pressure is maintained in the annulus between the drill stem pipe and the wall of the bore hole. The packer remains at this position with the drill stem sliding downwardly as the formation is drilled, through the packer mandrel or sleeve until the packer is deated by ports or grooves at a fixed interval above the ination means on the drill stem pipe.

When the packer'is deated, its weight and the hydrostatic pressure of the fluid in the annulus cause the packer unit to slide down the fixed interval to the inflation means which also serves to stop the packer unit. The force exerted by the dropping of the packer unit pushes open the ination valve thus reinilating the packer.

As drilling progresses the drill stem pipe then slides down through the packer mandrel until the deating means or splines on the drill pipe reach the packer at which time the packer is again deflated and again drops to the inflating means where the packer is again reinated. The deation and reinfiation cycle is repeated at fixed depth intervals as the drilling progresses in accordance with the vertical distance between the inflation means and the deliation means. This arrangement is very desirable and advantageous inasmuch as the packer is not required to slide downwardly along the wall of the hole in an inated position as the drill bit advances deeper into the earth. While the packer assembly slides downward, it is at least partially deated to the extent that there is no friction between the packer and the wall of the bore. The rotating and sliding motion is between the metal sleeve on which the packer is mounted and the drill stem only.

An object of this invention is to provide an in-iiatabledeatable packer that advances automatically downwardly step-wise, thus preventing sliding motion between the packer and the Wall of the well bore. A further objective of the invention is to provide a means for lowering the hydrostatic pressure in the space in which the drill bit is drilling to a pressure below that in the annulus between the drill pipe and the wall of the bore hole. Further objects of this invention will become apparent and more fully understood from the ensuing description and from the accompanying drawings in which:

` Figure 1 isa partial sectional vertical view of the packer unit mounted on a .tubular support within a well bore;

and

Figure 2 is similar to Figure l but shows the position of the inflatable Packer when it is iuated.

Figure 43 Villustrates-in section a verticalv view of an arrangement ofthe packer unit in'relation to a system in which the pressure surrounding the drill bit has been `reduced in relation to the pressure inthe annulus.

, Referring specifically to the drawing, itwill be seen that a .tubular support 10 which may be attached by tool joint .1v1 to an ordinary drill 'pipe suspended Vfrom the surface is suspended within bore hole 12,.y A tool joint 13 is provided at the lower end of t bular support 10 for attaching toa `drill bit, drill collar, etc. Slidable sleeve or packer mandrel 14 is positioned upon tubular support incorporated to the Y lheY packer 'murs-t offvalves'used is not norm-ally critical. Y Y

30 'isarranged to hold inllat-ion valve 28 Y valve Y section 16V and pushes against or strikesshoulder Vin'llation'.valve 28 thereby forcing the valve kplug 34 .Y pjackerijsfforced down by .gravity and the Yhyd'rostatie pressure of theiluid Vabove the packer in `the'zrinnulus between ythe drill stemY pipe andthe -Wall of VY within a recessed section `16 and is free to turn and slide in relation to tubular support member 10 within the `confines of recessed section16. Slidable sleeve 14 is provided with pacldngseals lil4 .whichmaintain a seal between ,the vsleeve Iand the surface of the recessed Yportion be. desirable to 4retainthe seals in grooves also provided rwith' atV least one but preferably several closely spaced ports 20 extending :through the sleeve. Atlxedto the outer surface Y of theV sleeve 1 4, and carried thereonY 'is' an inllatable packer 22 whichV is preferably made of rubber although various plasticseanvas or other fabrics..my be used- ASteelwire or other cord may be i packer fabric to ygive added'st-rength. possess sufficient elasticity to form Ya tight seal against the bore wall vwhen inflated even though Vthe lwall surfacemay be somewhat'irreg'ular becauseV of cave-ins and wash-outsg i i Y ln' the upper portion of recessed section 1 6, :thereis atleast one lbutpreferably several ldellating ponts or "grooves 24; These grooves are arranged to deflate packer 2 2 .when the packer assembly is atthe upper portion of recessed section 16. The lgrooves 24 break the seal Vbetween the packer sleeve and the wall of the recessed section ofthe tubular supporty or drill pipe. Whenf the packer is deilated,^it` will automatically drop to the lower 'portion lof recess section 16. section 16 is pro-rded 'with inil'ation meansconsis-ting of inflation c onduit26 .located within the walls .of tubular support 10,' and inllation valve 28 capable ofvopening and closing conduit Z5.A i Two valvesV ployedlasshown in'V the` drawing;however, the `number Valve'spri'ng isa closed-position. Shoulder-32 extends fromV inilation 28a'nd is arranged .to be in the vertical'pathof sleeve I4: the .tubular support 10 'within the connesof recessed 32 of Thelower portion of recess Y .2S-will 'normally be em- The packer unit after Vdeflation' slides down i the well bore. The mandrel or sleeve 174 of rthe packer assembly pushes valve 28 downwardly which Yopens the inilation valve 28 and the fluids in the bore of drill stem pipe 16 llow through inllation conduit 26 and ports 20 and reinilate packer 22.V As the `drill stem is lowered with subsequent drill-ing .the packer no'longer holds valve 28 in an open position, and spring-3l!` -forces Ithe valve shut. The pressure of the iluid within-the 'bore of the drill pipe also aids in holding the valve Closed. The vertical distance between the inllation meansland the deilatingY means may vary as. `desirable with the openati'on problems encounteredwbu-t for normal drilling operations-of-oiland gas wells will vary between about -5 feet toabout 60 feet.

The .pumps which drive the circulating lluid 'are stopped when the packer assembly is -being lowered into or being brought out of the hole. As the pumps are stopped the packer will not be -inilated Iby valve Y28 when coming out Vofthe hole although the packer normally being inthe lower-position of the Y.recess section will open valve128. The packer which yis used. should be of `antype which is normally deflated cujcollapsed.` Surges, if any, Tin the lluid in the drill string 'or `borehole will not ybe sullici'ent to inflate the packer. However, should a surge virillate the packer, the packer wil-l immediat-ely deilateif it is in vthe lower or the upper position. If'inV an intermediate position, .thepackerj is not inilated by surges' as the interiorof ythe packer is not in fluid commmlicationfwith the lluid in the )borehole or drill pipe. The packer is normally at 'the bottom of the recess when being lowered into or `being `withdrawn .fromthe hole, and the drag, if any, which .the packer may have with the wall of the `:bore hole is, very small as the packer is set 'in a recessed section and', being normally collapsed, the outerlsurface of the packer will normally liewithinwthe recessedjseetion and'will thus .be protected. j y( Sometimes' it may be necessary or desirableto stop drilling operations when .the packer is positioned `between the dellating and the inllating means. vBefore the"packer 'can be removed it must, ofcourse, `be deflated. however, poses noV problem nasmuchlas ,1211 Packer can be deflatedfby merelyliftingV Itheldrilling pipeand reducfrom seat 36 and openinglconduitl therebyestablishf ing diluid communication between the bore. 'of` tubular support member lllandrports 20 of sleeve 14. Ports 20 are in `c'ormnunication V'with the interiorfof packer 22. This alignment and communication is Aobtained when the packer assembly. is positioned in i the lower section 16;' A" stop 3 8 is provided of the inilation valve to prevent unnecessary strain yof Vthe valve lassembly and also-to assure that 1'4- are portion of recessed in properalignment for communication with con- As an Yexample of a normal operation, packer assembly `is mounted in recessed section 16 VVand is lowered Y vintoplace with packer l22finV ajdellated state. v."I'he Weight ofthe packer4 assemblyfresting upon or pushing against shoulder 32 willlpopen valve ZSfin inrtlation conduit Y As drilling luid'or other fluid is injected'und'er pressure Vinto the fboreo-fthe drill pipe, packer 22 be inllated.'

, After'fthe packer is inllated,Y Veipa'clcer assembly vdoes not move but isteadfis heldin' a fixed"positionY by the force ofgthe packerragains-t the of the packer assembly as drilling'pr'ogresses.

below.V shoulder 32 borehole wall, vwith vthe ldrillV stem rotatingfwithin and'sliding y'own throughA sleeve 14 pipe hasr passed downwardly `through groovesg24 'are at-the samedepth ing the uidpressure Vvwithin the bore offth'e drilll pipe. Ihe drill .pipej is lifted until the shoulder of the inflation unit thus opening Yvalve 28 and providing illuid' communi: cation betv/ een' the.ports 2l`:and the bore. of the drill stem..l The pressure holding the packer inatedfwill Vquiokly'lbe -bled off and .thepacker will be dell-ated.l f

' It is to abe understoodathat various typesfof inllatable v the ports of sleeve .lar member 42j l through return jasithe packer'assemmyhe packer :win be deseen/nn the Ypressurewithin' p K ports'20fand1dellationggrooves 24 which VareA not sealed by sealsflfS, As soon las thepackerjs suliciently de'ated to'relieve iction between th'e'wall'jof thewell bore, the

the packer` being releasedY vthrou also partiallyV by operation .at the Ydrill Yis provided" and mounted '.orijar'elcesseds im' lower the pressure infos 'area surrounding-'niente a conventional tool' joint l'as packers Ymaybe Vutilized in the invention whi'c'hhas been disclosed herein. `lt should' also he noted that this system inaylgbe used with various arrangements of drillingand testingdevices where itisldesired to isolate the Varea of ,the packer. Y

` As an example, this lpacker assembly mayfbeused V'in a drilling' operation such -as illustratediinfFigureS. A return l'citynduit1140.fis lo'e'atedwithfin a Y. `drilling fluid 'passes downwardly fthroughf-the'bore of @hu- Y th laf partofvlthe passmg thro nailing bn ass" injecter` ama1psesiihreagh ijefiparnp, which "operates seals the annular.space above 'the packer andfthe` area surrounding thedrill pipe.Y VAs -tleldiillingv advances,VV the the mandrel o-r sleeve of thepacker;

bit froman annular space above Y step-Wise and is reinated inthe Amanner described herein above. By the use of this arrangement as shown in Figure 3, the hydrostatic pressure surrounding the drill bit is maintained substantially less than that in the annulus above the packer. The reason that pressure on the bit is reduced is lthat jet pump 44 draws uid up through inlet 46. By reducing the pressure in the area in which the drill bit is drilling, the eiciency of the drilling operation will be greatly increased. It should be noted that the principle and operation of a jet pump such as the one used in Figure 3 is found in most mechanical engineering handbooks and also in many other publications. When the packer deates and slides down the recess section of 4the tubular support, the pressure about the bit may momentarily tend to increase; however, as soon as the packer reintiates, the jet pump again reduces the pressure in the borehole about the bit. The .time for the packer to deflate sufdciently .to slide down and be reinlated is very short as the packer will be forced down by its weight and the weight of .the fluid it is supporting as soon as the seal between the packers and the borehole wall is broken.

It is apparent that numerous modications and variations may be made in the apparatus described without departing from the spirit and scope of the present invention and it is intended that the invention be limited only by the scope of the following claims.

We claim:

l. An inflatable packer unit for use in a well bore which comprises a tubular support, a sleeve sealingly and slidahly mounted on the exterior of said tubular support with said sleeve having a port ltherein, an elastic packer mounted on the exterior of said sleeve with said packer being adapted to sealingly engage the wall of the well bore, ination means iixedly mounted at a rst position on said tubular support to be operative to inflate said elastic packer when said sleeve is at said irst position, and deation means in a second position spaced along said tubular support from said lrst position and operative to deflate said elastic packer when said sleeve is adjacent said second position.

2. An inflatable packer unit for use in a well bore which comprises a ltubular supporting having a recessed section on its outer peripher` a sleeve slidably, rotationally, and sealably mounted on lthe exterior of said tubular support in said recessed section and having at least one port extending therethrough, an elastic packer mounted on the exterior of said sleeve, at least one conduit in said tubular support near a iirst end portion of the recessed section of said tubular support and extending `from the bore of said tubular support to said recessed section, a valve Ibiased toward a closed position in said conduit, said valve having a shoulder member extending into said recessed section in the path of the longitudinal movement of said sleeve such that when said sleeve is disposed near said viirst end portion of said section said shoulder member is operative to open said valve, anddetiation means near the other end portion of said recessedV section operative to deflate said elastic packer when said sleeve is near the other end portion of said recessed section.

3. An inilatable packer unit for use in a Well bore which comprises a tubular support having a recessed section on its outer periphery, a sleeve slidably and rotationally mounted on the exterior of said tubular support in said recessed section and having at least one port extending therethrough, sealing means between said sleeve and said recessed section, an elastic packer mounted on the exterior of said sleeve, deation means comprising at least one groove in one portion of said recessed section d and extending beyond said recessed section adapted to deflate said packer when said packer and said sleeve are positioned around said groove whereby said groove tablishes `fluid communication between lthe interior of said packer and the exterior thereof, a-t least one inlation conduit in the wall of said tubular support near a second portion of the recessed section of said tubular support in liuid communication with the interior of said sleeve and the bore of said tubular support, a valve biased toward a closed position within said conduit, said valve having a shoulder member extending into said second portion of said recessed section in the longitudinal path of said sleeve so that said valve is opened when said sleeve is disposed near said second portion of said recessed section.

4. An inflatable packer unit for use in a Well bore which comprises a tubular support suspended in a well bore and having a recessed section on its outer periphery, a sleeve slidably, rotationally, and sealably mounted on the exterior of said tubular support in said recessed section and having at least one port extending therethrough, an elastic packer mounted on the exterior of said sleeve, deflation means comprising at least one groove in the upper end portion of said recessed section extending beyond said recessed section and arranged to establish tiuid communication between the yinterior of said packer and the exterior thereof when said packer and said sleeve is positioned Laround said groove thereby dellatng said packer, at least one ination conduit in the wall near the lower end portion of said recessed section of said tubular support and extending from the bore of said tubular support to said recessed section, a valve biased toward a closed position in said conduit, said valve having shoulder member extending into said recessed sect-ion in the path of said sleeve so that said valve is opened when said sleeve is disposed near said lower end portion of said recessed section.

5. An inatable packer unit for use in a well bore which comprises a tubular support suspended in a well bore and having a recessed section on its outer periphery, a sleeve slidably and rotationally mounted on -the exterior of said tubular support yin said recessed section and having -at least one port extending therethrough, sealing means between said sleeve and said recessed section, an elastic packer mounted on the exterior of said sleeve, deflation means comprising at least one groove in the upper end portion of said recessed section and extending beyond said recessed section and establishing uid communication between the interior of said packer and the exterior thereof when said packer and said sleeve are positioned around said groove thereby deating said packer, at least one inflation conduit in said tubular support near the lower end portion of said recessed section and extending from Within the interior of said sleeve to the bore of said tubular support, aV

valve biased toward a closed position in said conduit, -a valve spring arranged to hold said valve closed, said valve having a shoulder member extending radially into said recessed section whereby said shoulder member is adapted to receive said sleeve and operative to open said valve when said sleeve is disposed upon said shoulder.

References Cited in the tile of this patent UNTED STATES PATENTS 2,186,230 Bald Jan. 9, 1940 2,663,545 Grable Dec. 22, 1953 2,710,741 Hall .lune 14, 1955 2,783,028 Jamison Feb. 26, 1957 2,796,938 Lynes June 25, 1957 

